Reviewer: S. Randhawa, M.D., Allergist/Immunologist, Fort Lauderdale, FL
A 7-year-old boy is in the allergy clinic for evaluation for latex allergy. Three months ago, he had dental work done on 7 teeth on the same side (on the right) and 2-3 dental caps on the other side. The procedure lasted 22 minutes. Soon after, while in recovery, he developed facial angioedema. An allergic reaction to latex was presumed because the dentist used latex gloves. In the dental office, he received two epinephrine doises, antihistamines and Solu-Medrol IV (methylprednisolone). Despite that, it took about a week for the swelling to subside.
His specific IgE testing (sIgE) for latex (ImmunoCAP) was negative. However, ImmunoCAP test is only helpful if positive (similar to sIgE for penicillin). A negative specific IgE test for latex does not rule out latex allergy and he was scheduled for skin prick test and challenge with the same. The dentist provided the same type of latex glove that he worked with during the procedure.
Past Medical History, Past Surgical History, Social History are unremarkable. Medications: none. Physical Examination: unremarkable.
What is the differential diagnosis in this case?
- Latex allergy
- Postoperative facial edema secondary to local trauma
- Allergic reaction to anesthetic or antibiotic
What test would you suggest?
Skin prick testing with latex, followed by challenge if the skin test is negative.
He had skin prick testing with latex. It was performed with the same type of latex glove that the dentist was wearing during the 22-minute surgical procedure that was was followed by suspected angioedema.
The skin test was done with the prick-puncture technique with:
- negative/positive control
- wet glove
- wet glove solution
- dry glove
The skin prick test with latex was completely negative.
This was followed by a negative challenge test: with rubbing of the latex glove on his left hand, there was no reaction, and then the latex glove, with powder on, was rubbed on his right cheek, and again he had no reaction immediately, and then during the observation period, 40 minutes after the test. This is considered a negative skin prick and challenge test with latex.
Postoperative facial edema secondary to local trauma. There is no evidence of latex allergy, especially with negative skin prick test, specific IgE, and direct challenge with latex. The differential diagnosis includes an allergic reaction to anesthetic or antibiotic.
This is a patient with facial edema soon after dental procedure involving work on multiple teeth. It was initially attributed to latex, however, he had negative specific IgE testing for latex. Also, he had a negative skin prick test for latex today and a negative skin challenge with latex. In addition, he has a long history of exposure to latex products and they do not report any allergic reactions, including when he plays with balloons with latex powder.
There is no contraindication to using latex products or latex gloves during surgical procedures.
An approach to performing a test for immediate hypersensitivity to latex:
1. Prick test with the solution obtained from a soaked latex glove left in saline for one hour. Await 15 minutes.
2. If test 1. is negative, place a wet latex glove on the arm for 15 minutes.
3. If there is no response to test 2., prick through the wet latex glove. Await 15 minutes.
4. Simultaneously draw an ELISA for IgE-anti-latex (ImmunoCAP). Await the results of the ELISA before clearing for the surgical procedure.
Evaluation of patient with possible latex allergy. AAAAI Ask the Expert, 2012.
List of some common products that may contain latex
Rubber sink stoppers and sink mats
Rubber or rubber-grip utensils
Rubber electrical cords or water hoses
Bath mats and floor rugs that have rubber backing
Toothbrushes with rubber grips or handles
Rubber tub toys
Sanitary napkins (that contain rubber)
Diapers that contain rubber
Adult undergarments that contain rubber
Waterproof bed pads containing rubber
Undergarments, socks and other clothing with elastic bands that contain rubber
Adhesives such as glue, paste, art supplies, glue pens
Older Barbie dolls and other dolls that are made of rubber
Rubber bands, mouse and keyboard cords, desktop and chair pads, rubber stamps
Mouse and wrist pads containing rubber
Keyboards and calculators with rubber keys or switches
Pens with comfort grip or any rubber coating
Remote controllers for TVs or VCRs with rubber grips or keys
Camera, telescope or binocular eye pieces
Bathing caps and elastic in bathing suits
Tests to rule out latex allergy
- Skin prick test with the liquid from the soaked latex glove, and then if that is negative, apply a wet glove to the forearm and prick through the glove. If all of the above are negative using the same gloves the patient has used in the past it would make the diagnosis of latex allergy unlikely. This should be followed by a challenge when appropriate.
- Specific IgE blood test may be helpful but the skin testing is the preferred diagnostic method. sIgE for latex allergy has much lower sensitivity than previously reported - sensitivity was 35%; specificity 98% (Ann of Allergy, Asthma, Imm, 2012). Sensitivity, specificity, NPV, and PPV of latex-specific IgE assay are 91, 72, 96 and 50%, respectively (http://goo.gl/9gX0F).
- Pre- and post- pulmonary function tests as objective confirmation of obstruction if a patients complains of shortness of breath but did not exhibit visible cutaneous manifestations
Classification of adverse reactions to drugs: "SOAP III" mnemonic (click to enlarge the image):
Adverse drug reactions (ADRs) affect 10–20% of hospitalized patients and 25% of outpatients. Neuromuscular blocking agents, antibiotics, and latex are the most common causes of anesthesia-related reactions http://buff.ly/1kVa1Xk
Rule of 10s in ADR
10% of patients develop ADR
10% of these are due to allergy
10% of these lead to anaphylaxis
10% of these lead to death
Angioedema (AE) can be allergic or non-allergic.
There are 5 types of non-allergic angioedema (AE):
- acquired AE
- hereditary AE (HAE)
- ACE-inhibitor induced AE
- idiopathic AE, can occur with chronic urticaria
- pseudoallergic AE, e.g. reaction to NSAIDs
There are 3 types of HAE that are differentiated by C4 and C1-INH levels
- type I HAE - low C4, low C1-INH function, low C1-INH antigen level
- type II HAE - low C4, low C1-INH function, normal C1-INH antigen level
- type III HAE - all normal
Latex Allergy. Cleveland Clinic.
Latex-free Consumer Products. American Latex Allergy Association.
Latex Allergy. The American Family Physician, 1998.
A patient information handout on latex allergy.
Diagnosis of latex allergy. AAAAI Ask the Expert, 2011.
Approach putative reactions to local anesthetics by a skin test followed by a “graded challenge” protocol goo.gl/vJfQp
Contact dermatitis to latex surgical gloves? There are limited choices for non-latex gloves: vinyl or nitrile. AAAAI, 2011. Hypersensitivity reactions due to nitrile gloves - presence of latex was the cause of the symptoms (JACI, 2012).